was 7 years liveing with ic commom law marriage so after that time we start file married but come to find out tenn. has no common law marriage what do i need to do start file single or not will this get you called in by irs what should i do i made a mistake

we been live in the same house for 10 years together just like we were married i was told after 7 years it common law you are married in Tennessee
so we started filing jointly we thought it was law . Tennessee and in most other stats thats far form the Truth. wo we been doing this for 3 years what should we do we broke the law tring to do right? what should i do we don't realy want to get audit by the irs . or is this something they don't audit for .